This study was conducted to investigate commercial formulations of insecticides against western flower thrips, Frankliniella occidentalis (Pergande).The insects were collected from commercial greenhouses of cucumber in Varamin, Iran. The tested insecticides were diazinon (EC 60%), cypermethrin (EC 40%), fipronil (EC 2.5%), imidacloprid (SC 35%) and a botanical insecticide oxymatrine (Kingbo, AS 0.6%). Fipronil had the highest efficacy among all tested insecticides (LC50 = 17.97 ppm). However, imidacloprid had the lowest efficacy (LC50 = 2303 ppm). The oxymatrine was effective (LC50 = 69.94 ppm) after fipronil.
